[Anthony]

A little Tremec history .

The Tremec Company purchased the manufacturing rights to some of Ford's manual transmissions in the mid-Seventies and continued to build the Toploader, along with a three-speed unit, in Mexico for many OE production applications in Europe and elsewhere. During these years, Tremec was also inventing the TR-3550 five-speed that was later featured in the 1995 Mustangs Cobra R. Although this gearbox was originally designed for light commercial trucks, it found a home behind plenty of Ford's 5.0 engines after establishing a reputation for itself with Mustang enthusiasts as an excellent upgrade to the factory T-5 manual five-speed.When Tremec decided to increase the shaft sizes on both the input and output to strengthen the TR-3550 in 1994, the TKO series was born. By 1996, Tremec, now owned by Transmission Technologies, had purchased the transmission portion of Borg-Warner and used its steel gear designs to improve the TKO and produce a fifth-gear overdrive ratio of 0.83:1. New TKO-500 and -600 transmissions with a first gear ratio of 3.27:1 and an overdrive fifth gear ratio of 0.68:1 were released during 2004. The latest offering has performed exceptionally well in some 600-plus-lbs.ft. drag-race applications. It performed so well, in fact, that Tremec discontinued the TR-3550 and earlier versions of the TKO-500 and -600 in 2004 and '05.